ClamAV before 0.96 does not properly handle the (1) CAB and (2) 7z file formats, which allows remote attackers to bypass virus detection via a crafted archive that is compatible with standard archive utilities.
https://wwws.clamav.net/bugzilla/show_bug.cgi?id=1826
http://www.vupen.com/english/advisories/2010/1206
http://www.vupen.com/english/advisories/2010/1001
http://www.vupen.com/english/advisories/2010/0909
http://www.vupen.com/english/advisories/2010/0832
http://www.vupen.com/english/advisories/2010/0827
http://www.ubuntu.com/usn/USN-926-1
http://www.securityfocus.com/bid/39262
http://www.openwall.com/lists/oss-security/2010/04/08/3
http://www.openwall.com/lists/oss-security/2010/04/06/4
http://www.mandriva.com/security/advisories?name=MDVSA-2010:082
http://support.apple.com/kb/HT4312
http://secunia.com/advisories/39656
http://secunia.com/advisories/39329
http://secunia.com/advisories/39293
http://lists.opensuse.org/opensuse-security-announce/2010-04/msg00006.html
http://lists.apple.com/archives/security-announce/2010//Aug/msg00003.html
http://git.clamav.net/gitweb?p=clamav-devel.git%3Ba=blob_plain%3Bf=ChangeLog%3Bhb=clamav-0.96